Dual mode user interface system and method for 3D video

ABSTRACT

A system is provided for use with a video input signal and a video unit. The video input signal can be one of a two dimensional video signal and a three dimensional video signal. The video unit can display a three dimensional video and a two dimensional video. The system includes a receiver portion, a processing portion, a switching portion and an output portion. The receiver portion can receive the video input signal. The processing portion can output a first signal in a first mode of operation and can output a second signal in a second mode of operation, wherein the first signal is based on the video input signal and the second signal is based on the video input signal. The switching portion can switch the processing portion from the first mode of operation to the second mode of operation. The output portion can provide an output signal to the video unit, wherein the output signal is based on the first signal when the processing portion operates in the first mode of operation and wherein the output signal is based on the second signal when the processing portion operates in the second mode of operation. The first signal includes a two dimensional video signal, whereas the second signal includes a three dimensional video signal.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.13/181,536, filed Jul. 13, 2011, which is hereby incorporated byreference herein in its entirety.

BACKGROUND

A method used for creating a three dimensional (3D), or stereoscopic,image has been used for some time now, primarily in movie theaters. Itgenerally involves creating two images for each frame, one indented forthe left eye and one intended for the right. In movie theaters, theseimages are displayed simultaneously. The viewer wears specializedglasses that filter the appropriate images for each eye. Morespecifically, the left lens of the glasses filters out the right imageso the left eye only sees the left image. Similarly, the right lens ofthe glasses filters out the left image so the right eye only sees theright image. When the images are combined in the brain the illusion ofdepth is created and the viewer sees a “3D” image.

Modern televisions with 3D capability use a more complicated activeshutter method. Just as with movie theaters, two images are created foreach frame, one for the left eye and one for the right eye. The vieweralso must wear specialized glasses. However, instead of using filters todistribute the images to the appropriate eye, each lens closes, orshutters. The television also does not display the imagessimultaneously. In operation, the television displays the left image andthe right lens shutters allowing only the left eye to see the leftimage. Then, the television displays the right image and the left lensshutters allowing only the right eye to see the right image. Thisprocess repeats very rapidly and the viewer does not notice theshuttering. This is how the illusion of depth is created. While theactive shutter system is the most widely used 3D technology for thetelevision, passive/polarized lens systems are additionally on themarket. Further, there are systems that do not need glasses, althoughthey have significant draw backs when in the 3D mode.

The active shutter method creates a synchronizing issue, when there is a3D format change. For instance, when converting from a side-by-side 3Dformat to a top-to-bottom 3D format, the placement of the twoperspective changes. The television may be instructed of the switch, butit is not provided with any information about exactly when the changewill occur. Accordingly, the source of the 3D content changes format andthe television changes how it reads the content, but there is nosynchronization for the change. In other words, the television maychange format at a different time from the format change of the 3Dcontent from the source, resulting in a poor image.

The operation of a conventional television viewing system will now bedescribed with reference to FIG. 1.

FIG. 1 illustrates a conventional television viewing system 100 operableto display content from a television service provider (not shown).

Conventional television viewing system 100 includes a set-top box 102, avideo unit 104 and a remote control unit 106.

Set-top box 102 is arranged to receive an input signal 108 from atelevision service provider (not shown), to receive a remote controlsignal 112 and to output an output signal 110. Video unit 104 isarranged to receive output signal 110. Remote control unit 106 isarranged to output remote control signal 112.

Communication between any of the elements of conventional televisionviewing system 100 may be accomplished by way of any known communicationmedia. Signals typically embody computer-readable instructions, datastructures, program modules, or other data in a modulated data signalsuch as a carrier wave or other transport mechanism and include anyinformation-delivery media. Non-limiting examples of communicationsmedia between any of the elements of conventional television viewingsystem 100 include wired media, such as wired networks and direct-wiredconnections, and wireless media such as acoustic, radio-frequency,infrared, etc. The term “tangible computer-readable media” as usedherein includes both storage and communications media.

Further, in some embodiments at least one of the elements ofconventional television viewing system 100 may be implemented astangible computer-readable media for carrying or havingcomputer-executable instructions or data structures stored thereon. Suchtangible computer-readable media can be any available media that can beaccessed by a general purpose or special purpose computer. Non-limitingexamples of tangible computer-readable media include physical storageand/or memory media such as RAM, ROM, EEPROM, CD-ROM or other opticaldisk storage, magnetic disk storage or other magnetic storage devices,or any other medium which can be used to carry or store desired programcode means in the form of computer-executable instructions or datastructures and which can be accessed by a general purpose or specialpurpose computer. When information is transferred or provided over anetwork or another communications connection (hardwired and/or wireless,or a combination of hardwired or wireless) to a computer, the computerproperly views the connection as a tangible computer-readable medium.Thus, any such connection is properly termed a tangiblecomputer-readable medium. Combinations of the above should also beincluded within the scope of tangible computer-readable media.

Remote control unit 106 is operable to send commands from the user toset-top box 102. Non-limiting examples of commands include those forchanging the channel, displaying content information and displaying thechannel guide. Set-top box 102 is operable to process television contentfrom input signal 108 into an appropriate signal for video unit 104.Video unit 104 is operable to display video and to play audio contentprocessed by set-top box 102. Non-limiting examples of video unit 104include a television, hand-held communication device and a computer.

In operation, the user would utilize remote control unit 106 to sendcommands to set-top box 102. For the purposes of explanation, assumethat a command or series of commands are used to select a channel.Remote control unit 106 would send the command or commands throughremote control signal 112. Remote control unit 106 may be any knownremote control unit, non-limiting examples of which include a computer,a cellular phone, and a dedicated remote.

Once set-top box 102 has received remote control signal 112, set-top box102 will then process input signal 108 and create output signal 110.Video unit 104 then presents the audio and video included in outputsignal 110 to the user.

A more detailed description of the operation of set-top box 102 will nowbe described with reference to FIG. 2.

FIG. 2 illustrates an example block diagram of set-top box 102 of FIG.1.

As illustrated in FIG. 2, set-top box 102 includes a receiver portion202, a decoder 204, a compositor 206, a graphics device 208 and anoutput portion 210.

Receiver portion 202 is arranged to receive input signal 108 and tooutput input data 212. Decoder 204 is arranged to receive input data 212and to output decoded data 214. Graphics device 208 is arranged tooutput display graphics 216. Compositor 206 is arranged to receivedecoded data 214, to receive display graphics 216 and to outputcomposite data 218. Output portion 210 is arranged to receive compositedata 218 and to output output signal 110.

Receiver portion 202 is operable to perform many functions. At aminimum, receiver portion 202 performs the function of a tuner. A tunerretrieves the appropriate channel data from input signal 108. In anotherexample, receiver portion 202 may also perform the function of adecrypter. A decrypter is needed if input signal 108 is encrypted.

Decoder 204 is operable to decompress compressed data. A non-limitingexample of a compressed data type is MPEG4.

Graphics device 208 is operable to generate the display graphics and mayinclude multiple portions. These portions may include memory wheregraphics are stored and a graphics processor. Non-limiting examples ofdisplay graphics include a channel guide and content information.

Compositor 206 combines the video with display graphics. A non-limitingscenario of combining video with display graphics includes when thechannel guide is called by the user. In this example, compositor 206 mayshrink the channel video and place the channel video in the upper rightcorner of the channel guide.

Output portion 210 is operable to interface the content to be displayedwith video unit 104. A non-limiting example of a television interface isHDMI.

In operation, input signal 108 is received by receiver portion 202.Input signal 108 includes data for a multitude of channels provided bythe television service provider. Data for each channel includes audiodata, video data and meta-data.

Meta-data is used by devices to determine the format of the channelvideo data. There are a multitude of possible formats for channel video.For 2D video, the format can be one of many resolutions. For 3D video,the 2D format parameters are augmented by parameters to describe how toderive both (or more) perspectives. One example 3D format is the lefteye image on the left, the right eye image on the right and both imagesat the same resolution.

Returning to FIG. 2, receiver portion 202 may perform multiplefunctions, a non-limiting example of which includes tuning. In thisexample, assume receiver portion 202 only acts as a tuner. In this case,receiver portion 202 filters out all data except for the data for thechannel selected by the user. This is input data 212 and includes, butis not limited to, audio data, video data, and meta-data. Input data 212is then transmitted to decoder 204.

Decoder 204 then decompresses input data 212. It is common fortelevision service providers to compress the data sent to the users.This data must be decompressed before further processing can begin. Anexample compressed data file format is MPEG4. Decompressed data 214 isthen sent to compositor 206. Compositor 206 also receives informationfrom graphics device 208.

When necessary, graphics device 208 creates the graphics that will bedisplayed on the television. The graphics than can be displayed includeat least one of the group including the channel guide, video informationand subtitles. The graphics that will be displayed can be chosen, forexample, by the user using remote control unit 106, or software (notshown) in set-top box 102. Once the appropriate graphics have beengenerated, display graphics 216 is set to compositor 206.

Compositor 206 will combine decoded data 214 and display graphics 216into one signal. Compositor 206 also determines how the channel videoand graphics will be displayed on the screen. For example, when the usersends a command to display information on the program being displayed,compositor 206 will overlay display graphics 216 on decoded data 214,creating composite data 218, which is then sent to output portion 210.

In the event graphics are not to be displayed, compositor 206 does notcombine graphics with decoded date 214. In this case, composite data 218only includes decoded data 214.

Output portion 210 converts composite data 218 into a data formatcompatible with video unit 104, creating output signal 110. A commonformat type for high definition televisions is HDMI. Output signal 110includes the same audio data and video data received by receiver portion202. An HDMI interface (not shown) returns the television'scapabilities, which can be used for selecting the preferred videoformat.

Referring to FIG. 1, video unit 104 will now display the video and playthe audio from the channel selected by the user. For the purposes ofexplanation, assume the video format of the current channel does notmatch the video format of the previous channel. In this case, video unit104 would need to change video formats to match the video format of thevideo data. This would cause video unit 104 to re-synchronize with thevideo data, resulting in an ugly transition in the video.

If the transition is from a channel displaying 3D content to a channeldisplaying 2D content, the user can watch the 2D content while wearing3D glasses. The glasses are awkward to wear, so people generally taketheir glasses off when they are not needed. If the transition is from achannel displaying 2D content to a channel displaying 3D content, theuser will need to find and wear the 3D viewing glasses. If thetransition is from a channel displaying 3D content in one video formatto a channel displaying 3D content in another video format, there willbe an ugly transition between the channel videos. What is needed is amethod of switching between channels of different video formats withoutcausing an action by the user or interrupted video clarity.

In view of the foregoing, there is a need for improved techniques forproviding switching between channels of different video formats withoutcausing an action by the user or interrupted video clarity.

BRIEF SUMMARY

In accordance with example embodiments of the present invention, asystem and method is provided for switching between channels ofdifferent video formats without causing an action by the user orinterrupted video clarity.

A system is provided for use with a video input signal and a video unit.The video input signal can be one of a two dimensional video signal anda three dimensional video signal. The video unit can display a threedimensional video and a two dimensional video. The system includes areceiver portion, a processing portion, a switching portion and anoutput portion. The receiver portion can receive the video input signal.The processing portion can output a first signal in a first mode ofoperation and can output a second signal in a second mode of operation,wherein the first signal is based on the video input signal and thesecond signal is based on the video input signal. The switching portioncan switch the processing portion from the first mode of operation tothe second mode of operation. The output portion can provide an outputsignal to the video unit, wherein the output signal is based on thefirst signal when the processing portion operates in the first mode ofoperation and wherein the output signal is based on the second signalwhen the processing portion operates in the second mode of operation.The first signal includes a two dimensional video signal, whereas thesecond signal includes a three dimensional video signal.

Additional advantages and novel features of the invention are set forthin part in the description which follows, and in part will becomeapparent to those skilled in the art upon examination of the followingor may be learned by practice of the invention. The advantages of theinvention may be realized and attained by means of the instrumentalitiesand combinations particularly pointed out in the appended claims.

BRIEF SUMMARY OF THE DRAWINGS

The accompanying drawings, which are incorporated in and form a part ofthe specification, illustrate an exemplary embodiment of the presentinvention and, together with the description, serve to explain theprinciples of the invention. In the drawings:

FIG. 1 illustrates a conventional television viewing system;

FIG. 2 illustrates an example block diagram of set-top box of FIG. 1;

FIG. 3 illustrates an example dual-mode television viewing system inaccordance with aspects of the present invention;

FIG. 4 illustrates an example block diagram of the set-top box of FIG.3;

FIG. 5 illustrates another example block diagram of the set-top box ofFIG. 3;

FIG. 6 contains example methods for converting from an input videoformat to an output video format in accordance with aspects of thepresent invention;

FIG. 7 illustrates an example method of operating the dual-modetelevision viewing system of FIG. 3; and

FIG. 8 illustrates another example method of operating the dual-modetelevision viewing system of FIG. 3.

DETAILED DESCRIPTION

In accordance with aspects of the present invention, a set-top box in atelevision viewing system will have two modes of operation, a 2D modeand a 3D mode. In the 2D mode, all content may be presented as 2D,wherein 3D content may be converted to 2D. In an example embodiment, 3Dcontent may be converted to 2D by eliminating a stereoscopicperspective. In the 3D mode, all content may be presented as 3D, whereingraphics, e.g. user interface content, etc., will seem to float abovethe video and may be rendered for each individual eye's perspective.Further, in the 3D mode, 2D content may be presented as flat, or may beconverted to 3D.

An example television viewing system in accordance with an aspect of thepresent invention will now be described with reference to FIGS. 3-6.

An example television viewing system in accordance with an aspect of thepresent invention will now be described with reference to FIG. 3.

FIG. 3 illustrates an example dual-mode television viewing system 300 inaccordance with aspects of the present invention.

As illustrated in FIG. 3, dual-mode television viewing system 300includes of a set-top box 302, a remote control unit 304 and video unit104.

Set-top box 302 is arranged to receive an input signal 108 from atelevision service provider (not shown), to receive a remote controlsignal 308 and to output an output signal 306. Video unit 104 isarranged to receive output signal 306. Remote control unit 304 isarranged to output remote control signal 308.

Remote control unit 304 is operable to send commands from the user toset-top box 302. Non-limiting examples of commands include those forchanging the channel, displaying content information and displaying thechannel guide. Set-top box 302 is operable to process television contentfrom input signal 108 into an appropriate signal for video unit 104.Video unit 104 is operable to display video and to play audio contentprocessed by set-top box 302.

In operation, the user would utilize remote control unit 304 to sendcommands to set-top box 302. For the purposes of explanation, assumethat a command or series of commands are used to select a channel.Remote control unit 304 would send the command or commands throughremote control signal 308.

Once set-top box 302 has received remote control signal 308, set-top box302 will then process input signal 108 and create output signal 306. Amore detailed description of the operation of set-top box 302 will nowbe described with reference to FIG. 4.

FIG. 4 illustrates an example block diagram of set-top box 302 of FIG.3.

As illustrated in FIG. 4, set-top box 302 comprises of a receiverportion 402, a processing portion 404, a switching portion 406 and anoutput portion 408. In this example, each of receiver portion 402,processing portion 404, switching portion 406 and output portion 408 aredistinct devices. However, in other embodiments, at least two ofreceiver portion 402, processing portion 404, switching portion 406 andoutput portion 408 may be combined as a unitary device. Further, in someembodiments at least one of receiver portion 402, processing portion404, switching portion 406 and output portion 408 may be implemented astangible computer-readable media for carrying or havingcomputer-executable instructions or data structures stored thereon.

Receiver portion 402 is arranged to receive input signal 108 and tooutput input data 410. Processing portion 404 is arranged to receiveinput data 410, to receive a switching signal 412, to output a 2D signal414 and to output a 3D signal 416. Switching portion 406 is arranged tooutput switching signal 412. Output portion 408 is arranged to receive2D signal 414, to receive 3D signal 416 and to output output signal 306.

Receiver portion 402 is operable to perform many functions. In thisexample, receiver portion 402 performs the function of a tuner. Inanother example, receiver portion 402 may also perform the function of adecrypter. A decrypter is needed if input signal 108 is encrypted.

Processing portion 404 is operable to process the output of receiverportion 402.

Switching portion 406 allows the user to select the output mode ofset-top box 302. A method for operating switching portion 406 mayinclude engaging a physical switch on set-top box 302. Of course in someembodiments, set-top box 302 may provide a 2D and a 3D signalconcurrently, wherein a TV may determine which signal to use fordisplay.

Output portion 408 is operable to interface the content to be displayedwith video unit 104. A non-limiting example of a television interface isHDMI.

In operation, input signal 108 is received by receiver portion 402.Input signal 108 includes data for a multitude of channels provided bythe television service provider. Data for each channel includes audiodata, video data and meta-data. As discussed previously, receiverportion 402 may perform multiple functions, but must at least performthe function of a tuner. In this example, assume receiver portion 402only acts as a tuner. In this case, receiver portion 402 filters out alldata except for the data for the channel selected by the user. This isinput data 410 and includes, but is not limited to, audio data, videodata, and meta-data. Input data 410 is then transmitted to processingportion 404. Processing portion 404 also receives a signal fromswitching portion 406.

Switching portion 406 allows the user to select the output video format.For example, switching portion 406 can be a physical switch on set-topbox 302, a remotely controllable switch (controllable by remote controlunit 304), software (not shown) within set-top box 302, or a combinationthereof. Once the output format has been selected, switching signal 412is sent to processing portion 404.

Processing portion 404 processes and converts the video data portion ofinput data 410 into the proper video format. In other words, the outputvideo format of processing portion 404 is determined by switching signal412, not by the video format of input data 410. For instance, assume thevideo format of input data 410 is 3D left/right with full resolution,and assume that the user has selected a 2D format with switching portion406, which is relayed to processing portion 404 by switching signal 412.In this example, processing portion 404 would convert the 3D video into2D video, and output 2D signal 414.

In another example, assume the video format of input data 410 is 3Dtop/bottom with full resolution and the user has selected a 3D formatwith left/right orientation. Processing portion 404 would convert thevideo format of input signal 410 into the 3D format selected by the userand would output 3D signal 416.

A case also exists where the video format of input signal 410 would bethe same as the user selected video format. In this case, the video datain input signal 410 would pass through processing portion 404 withoutconversion.

In any case, processing portion 404 will either output 2d signal 414 or3D signal 416 for further processing by output portion 408.

Output portion 408 will convert 2D signal 414 or 3D signal 416 into asignal that is compatible with video unit 104. A common format type forHD television interface is HDMI. This converted signal is output signal306. Output signal 306 includes video data and audio data for thechannel selected by the user.

Returning to FIG. 3, video unit 104 will receive output signal 306 andplay the audio and video data from output signal 306. For the purposesof explanation, assume the video format of the current channel does notmatch the video format of the previous channel. In the previous examplein FIG. 1, video unit 104 would need to change video formats to matchthe video format of the video data. This would cause video unit 104 tore-synchronize with the video data, resulting in an ugly transitionbetween channel video. In the example of FIG. 3, the video format ofoutput signal 306 has been matched to the video format of video unit 104by set-top box 302.

If the transition is from 3D content to 2D content, the user can watchthe 2D content while wearing 3D glasses. However, in accordance withaspects of the present invention, there is a continuity of style andlook of the user interface. If the transition is from 2D content to 3Dcontent, the user will not need to find and wear the 3D viewing glasses.If the transition is from 3D content in one video format to 3D contentin another video format, there will be a smooth transition between thechannel videos. The operation of dual-mode television viewing system 300will now be further explained with reference to FIG. 5.

FIG. 5 illustrates an example method of operating a television viewingsystem in accordance with an aspect of the present invention.

FIG. 5 shows an example processing portion 404 in accordance withaspects of the present invention. In this example, processing portion404 includes a decoder 502, a format conversion engine 504, a compositor506 and a graphics device 508. In this example, each of decoder 502,format conversion engine 504, compositor 506 and graphics device 508 aredistinct devices. However, in other embodiments, at least two of decoder502, format conversion engine 504, compositor 506 and graphics device508 may be combined as a unitary device. Further, in some embodiments atleast one of decoder 502, format conversion engine 504, compositor 506and graphics device 508 may be implemented as tangible computer-readablemedia for carrying or having computer-executable instructions or datastructures stored thereon.

As previously explained with reference to FIG. 4, input signal 108 isreceived by receiver portion 402. As discussed previously, receiverportion 402 may perform multiple functions, non-limiting examples ofwhich include tuning. In this example, assume receiver portion 402 onlyacts as a tuner. In this case, receiver portion 402 filters out all dataexcept for the data for the channel selected by the user, i.e., inputdata 410, non-limiting examples of which include audio data, video data,and meta-data. Input data 410 is then transmitted to decoder 502.

Decoder 502 then decompresses input data 410. It is common fortelevision service providers to compress the data sent to the users.This data must be decompressed before further processing can begin. Anexample compressed data file format is MPEG4. Decompressed data 510 isthen transmitted to format conversion engine 504. Format conversionengine 504 also receives a signal from switching portion 406.

Switching portion 406 allows the user to select the output video format,which may generally indicate more than a selection between 2D and 3D.For example, the television may suggests it's preferred video formatssuch as aspect ratio, resolution and supported 3D formats via the HDMIextended display identification data (EDID). The EDID, a data structureprovided by video display describing its capabilities to a video source,and perhaps other configurations, may be used in the selection offormats for both the 2D and the 3D modes. In an example embodiment, theuser will be aware of two output modes: 2D and 3D. If video unit 104does not support 3D content, then the 3D output mode will not beavailable. Once the output format has been selected, switching signal412 is sent to format conversion engine 504.

Format conversion engine 504 determines if the video format ofdecompressed data 510 needs to be converted. The input video format isidentified by the meta-data, which may be located within decompresseddata 510. If the video format of decompressed data 510 matches the videoformat selected using switching portion 406, then no conversion isnecessary. Decompressed data 510 then becomes formatted data 512 and istransmitted to compositor 506.

If the video format of decompressed data 510 does not match the videoformat selected using switching portion 406, then format conversionengine 504 converts the video data into the format selected usingswitching portion 406.

Before the conversion of the input video format can take place, formatconversion engine 504 may determine the correct output video format.Video unit 104 is capable of displaying one type or many types of videoformats. Video unit 104 will provide set-top box 302 with the formats itcan display, and the preferred format. Format conversion engine 504 maythen select the appropriate video format based on switching signal 412.

There are many different formats for both 2D and 3D video. A 2D videoformat includes parameters such as resolution and video refresh rate. A3D video format includes the 2D parameters in addition to the 3D formatselection, e.g., side-by-side, top/bottom, etc. Example methods forconverting between these video formats will be explained with referenceto FIG. 6.

FIG. 6 contains example methods for converting from an input videoformat to an output video format in accordance with aspects of thepresent invention.

FIG. 6 includes a column 602, a column 604, a column 606, a column 608,a row 610, a row 612, a row 614 and a row 616. Column 602, column 604,column 606 and column 608 correspond to possible input video formats.Row 610, row 612, row 614 and row 616 correspond to possible outputvideo formats. The intersection of each row and column shows the actionsformat conversion engine 504 must take to convert from the input videoformat to the output video format. In general, in accordance withaspects of the present invention, a set-top box may ask the televisionfor its preferred 2D format parameters and then converts the input videothat that format before sending it to the television.

The intersection of column 602 and 610 shows the actions to be performedwhen the input video format is 2D and the output video format is 2D. Inthis instance, format conversion engine 504 would scale the video asneeded to match the 2D format of video unit 104.

The intersection of column 602 and 612 shows the actions to be performedwhen the input video format is 2D and the output video format is 3Dside-by-side at half resolution. In this instance, format conversionengine 504 would shrink each video frame horizontally by half and maketwo side-by-side copies to fill a single output frame.

The intersection of column 602 and 614 shows the actions to be performedwhen the input video format is 2D and the output video format is 3Dside-by-side at full resolution. In this instance, format conversionengine 504 would copy each video frame into two consecutive outputframes.

The intersection of column 602 and 616 shows the actions to be performedwhen the input video format is 2D and the output video format is 3D topand bottom. In this instance, format conversion engine 504 would shrinkeach video frame vertically by half and create both a top and a bottomcopy to fill a single output frame.

The intersection of column 604 and 610 shows the actions to be performedwhen the input video format is 3D side-by-side at half resolution andthe output video format is 2D. In this instance, format conversionengine 504 would stretch the left image to match the 2D resolution ofvideo unit 104 and discard the right image. In another embodiment, theleft image may be discarded, wherein the right image would be stretchedto the left to fill a single output frame.

The intersection of column 604 and 612 shows the actions to be performedwhen the input video format is 3D side-by-side at half resolution andthe output video format is 3D side-by-side at half resolution. In thisinstance, format conversion engine 504 would perform no action and passthe input video through in altered.

The intersection of column 604 and 614 shows the actions to be performedwhen the input video format is 3D side-by-side at half resolution andthe output video format is 3D side-by-side at full resolution. In thisinstance, format conversion engine 504 would stretch each half frameperspective horizontally and copy as a complete output frame.

The intersection of column 604 and 616 shows the actions to be performedwhen the input video format is 3D side-by-side at half resolution andthe output video format is 3D top and bottom. In this instance, formatconversion engine 504 would shrink vertically and stretch horizontallyboth the right and left images and relocate to top and bottomorientation.

The intersection of column 606 and 610 shows the actions to be performedwhen the input video format is 3D side-by-side at full resolution andthe output video format is 2D. In this instance, format conversionengine 504 would discard every other frame to keep either the left orright perspective and to eliminate the other.

The intersection of column 606 and 612 shows the actions to be performedwhen the input video format is 3D side-by-side at full resolution andthe output video format is 3D side-by-side at half resolution. In thisinstance, format conversion engine 504 would collect sequential pairs offrames (containing both a left and right perspective) and pack them intoa single output frame by shrinking them horizontally.

The intersection of column 606 and 614 shows the actions to be performedwhen the input video format is 3D side-by-side at full resolution andthe output video format is 3D side-by-side at full resolution. In thisinstance, format conversion engine 504 would perform no action and passthe input video through in altered.

The intersection of column 606 and 616 shows the actions to be performedwhen the input video format is 3D side-by-side at full resolution andthe output video format is 3D top and bottom. In this instance, formatconversion engine 504 would collect sequential pairs of frames(containing both a left and right perspective) and pack them into asingle output frame by shrinking them vertically and placing the secondunder the first.

The intersection of column 608 and 610 shows the actions to be performedwhen the input video format is 3D top and bottom and the output videoformat is 2D. In this instance, format conversion engine 504 wouldstretch the top image to match the 2D resolution of video unit 104 anddiscard the bottom image.

The intersection of column 608 and 612 shows the actions to be performedwhen the input video format is 3D top and bottom and the output videoformat is 3D side-by-side at half resolution. In this instance, formatconversion engine 504 would shrink horizontally and stretch verticallyboth the top and bottom images and relocate to a side-by-sideorientation.

The intersection of column 608 and 614 shows the actions to be performedwhen the input video format is 3D top and bottom and the output videoformat is 3D side-by-side at full resolution. In this instance, formatconversion engine 504 would stretch each half frame vertically and copyas a complete output frame.

The intersection of column 608 and 616 shows the actions to be performedwhen the input video format is 3D top and bottom and the output videoformat is 3D top and bottom. In this instance, format conversion engine504 would perform no action and pass the input video through in altered.

As previously explained, set-top box 302 will identify which 3D videomodes are available with video unit 104. Based on which modes areavailable, format conversion engine 504 will determine the best formatfor the output video. If full resolution 50 Hz or better is available,that will be selected and used exclusively for 3D mode. In 3D mode, allinput formats will be converted to this format, and there should be noloss of quality in that conversion. If either video unit 104 or set-topbox 302 does not support full resolution 60 Hz, then half resolutionside-by-side or top-bottom will be used.

When entering 3D mode, an output format is selected that is supported byvideo unit 104, and best matches the format of the current video source.If the input source is 2D, side-by-side will be selected because it ismore popular.

While set-top box 302 is in 3D output mode and the 3D format of theinput video changes, after a few seconds the 3D output format willchange to match. This may cause the video unit 104 to re-synchronize,but the resolution should improve. The goal of the delay is to avoidre-synchronizing while flipping through channels, and to only adjustonce the user has settled on a channel. This transition may be performedwhen the conversion from the 3D format of the new source to the current3D output format is more lossy than another 3D format supported by thetelevision, e.g., if the television does not support full resolutionside-by-side, but is supports both half-resolution side-by-side andtop/bottom. Tuning from a side-by-side channel to a top/bottom channelmay leave the output format in the side-by-side mode. In such a case,the video quality may be degraded, and should be corrected.

Once the video data has been converted, formatted data 512 istransmitted to compositor 506. Compositor 506 also receives informationfrom graphics device 508.

When necessary, graphics device 508 creates the graphics that will bedisplayed on the television. Non-limiting examples of graphics that maybe displayed include the channel guide, video information or subtitles.The graphics that will be displayed can be chosen, for example, by theuser using remote control unit 304, or software (not shown) in set-topbox 302. Once the appropriate graphics have been generated, displaygraphics 514 are provided to compositor 506.

Compositor 506 will combine formatted data 512 and display graphics 514into one signal. Compositor 506 also determines how the channel videoand graphics will be displayed on the screen. For example, when the usersends a command to display information in front of the program beingdisplayed, compositor 506 will overlay display graphics 514 on the videodata portion of formatted data 512, creating composite data 516, whichis then sent to output portion 408.

In the event graphics are not to be displayed, compositor 506 does notcombine graphics with the video data portion of formatted data 512. Inthis case, composite data 516 only includes formatted data 512.

Output portion 408 will convert composite data 516 into a signal that iscompatible with video unit 104. A common format type for HD televisioninterface is HDMI. This converted signal is output signal 306. Outputsignal 306 includes video data and audio data for the channel selectedby the user.

Example methods for using dual-mode television viewing system 300 ofFIG. 3 will now be described in detail with reference to FIGS. 7-8.

Method 700 of FIG. 7 is drawn to the situation where a user is watchingtelevision and decides to change the channel.

As shown in the figure, method 700 starts (S702) and the user iswatching television (S704). For example, referencing FIG. 4, the tunerportion of receiver portion 402 filters out all data except for the datafor the channel the user is watching. Non-limiting examples of inputdata 410 include, audio data, video data, and meta-data. The data isthen decoded. For example, as illustrated in FIG. 5, input data 410 isthen decompressed by decoder 502, and decompressed data 510 istransmitted to format conversion engine 504.

Input data 410 is of a particular mode, i.e., 2D or 3D, and is of aparticular format, e.g., a specific scale, or resolution as discussedabove with reference to FIG. 6. For purposes of explanation, presumethat at this point the format of the input data matched the formatrequired by the television (if not, then the formats will be matched asdiscussed with reference to S710 as discussed below).

It is then determined whether the channel is changed (S706). Forexample, the user selects a new desired channel. As shown in FIG. 3,remote control unit 304 may be used to select the desired channel andcommands are sent to set-top box 302 through remote control signal 308.

If the channel is not changed, the user continues to watch television onthe current channel (S704).

If the channel is changed, the user selects the desired channel (S708).For example, referencing FIG. 3, remote control unit 304 may be used toselect the desired channel and commands are sent to set-top box 302through remote control signal 308. Referencing FIG. 4, the tuner portionof receiver portion 402 filters out all data except for the data for thechannel selected by the user. Non-limiting examples of input data 410include audio data, video data, and meta-data. As illustrated in FIG. 5,input data 410 is then decompressed by decoder 502, and decompresseddata 510 is transmitted to format conversion engine 504.

Returning to FIG. 7, once the channel is changed (S708), it isdetermined whether the format of the input data is the same as theoutput format required by the television (S710). For example, asillustrated in FIG. 5, input data 410 is then decompressed by decoder502, and decompressed data 510 is transmitted to format conversionengine 504. At this point, the channel format is compared to the formatsupported by the video unit. For example, format conversion engine thencompares the video format of decompressed data 510 and the video formatselected by switching portion 406.

In another embodiment, rather than determine whether the format of theinput data is the same as the output format required by the televisionas discussed above (S710), it may be determined whether the format ofthe new input data from the new channel matches the format of the inputdata from the old channel. If this is the case, the new input data ismerely passed through or scaled as needed.

If it is determined that the format of the input data is not the same asthe output format required by the television (or it is determined thatthe input data corresponding to the new channel does not match the inputdata corresponding to the old channel), then the format of the inputdata is changed (S712). For example, conversion engine 504 may convertthe video data. As previously discussed, methods already exist forconverting various video formats on another. For example, converting a2D video frame into a full resolution side-by-side 3D video frameinvolves copying the 2D frame into two consecutive output frames. Inanother example, converting a full resolution side-by-side 3D frame intoa 2D frame involves deleting every other frame. No matter theconversion, format conversion engine 504 is capable of each. Onceconversion is complete, the process moves to forward and formatted data512 is transmitted to compositor 506.

At this point, method 700 stops (S714).

In another situation, the user may want to switch modes, e.g., from acurrent 3D mode to a 2D mode or from a current 2D mode to a 3D mode.This will be described with reference to method 800 of FIG. 8.

As shown in the figure, method 800 starts (S702) and the user iswatching television (S704) in a manner similar to that discussed abovewith reference to FIG. 7.

It is then determined whether the mode is to be changed (S802). Forexample, the use first decides whether they want to watch in 2D or 3D.If the user wants to watch in 3D and has the 3D glasses, then they maychoose 3D.

If the mode is not to be changed, then the user continues to watchtelevision (S704). Alternatively, if the mode is to be changed, the userchanges the mode (S804). For example, returning to FIG. 4, the userselects the mode using switching portion 406. As previously explained,switching portion 406 can be a physical switch on set-top box 302, aremotely controllable switch (controllable by remote control unit 304),software (not shown) within set-top box 302, or a combination thereof.

After the mode is changed, the output format is chosen based on the bestsupported format listed in the EDID. For example, if full-resolutionside-by-side is a supported 3D format, then full-resolution side-by-sideis the selected 3D output format. Further, if the television does notsupport full-resolution, a lower resolution format is picked. Stillfurther, if the current tuned channel is 3D, the 3D input format couldbe selected as the output format.

Additionally, graphics may be added to the input data. For example,returning to FIG. 5, formatted data 512 is first transmitted tocompositor 506. Then any graphics, if necessary, may be added to thevideo data. As previously discussed, when necessary, graphics device 508creates the graphics that will be displayed on the television. Thegraphics that will be displayed can be chosen, for example, by the userusing remote control unit 304, or software (not shown) in set-top box302. Once the appropriate graphics have been generated, display graphics514 is set to compositor 506.

Compositor 506 will combine formatted data 512 and display graphics 514into one signal. Compositor 506 also determines how the channel videoand graphics will be displayed on the screen. For example, when the usersends a command to display information on the program being displayed,compositor 506 will overlay display graphics 514 on the video dataportion of formatted data 512, creating composite data 516, which isthen sent to output portion 408.

In the event graphics are not to be displayed, compositor 506 does notcombine graphics with the video data portion of formatted data 512. Inthis case, composite data 516 only includes formatted data 512. Outputportion 408 will convert composite data 516 into a signal that iscompatible with the video unit. A common format type for HD televisioninterface is HDMI. This converted signal is output signal 306. Outputsignal 306 includes video data and audio data for the channel selectedby the user. Then the combined graphics and video data are provided tothe video unit. The video and audio content for the desired channel willbe presented by video unit 104. At this point, method 800 stops (S714).

In short, when watching television in accordance with aspects of thepresent invention, a user may perform one of three actions: 1) continueto watch television on the current channel in the current mode; 2)change the channel; or change the mode (from 3D to 2D or from 2D to 3D).If the user merely continues to watch television, then there is nochange in the mode or the format. If the user changes the channel, theremay be a change in the format of the input data, which is taken intoaccount via method 700 of FIG. 7. If the user changes the mode, then thechanges in the output are taken into account via method 800 of FIG. 8.Finally, there may be situations where the format of a channel changeswithout the intervention of a user, such as when a 3D movie follows a 2Dmovie on the same channel. In these situations, the changes in theoutput are taken into account via steps S710 and S712 of method 700 ofFIG. 7.

In accordance with aspects of the present invention, a set-top box in atelevision viewing system will have two modes of operation, a 2D modeand a 3D mode. In the 2D mode, all content may be presented as 2D,wherein 3D content may be converted to 2D. In the 3D mode, all contentmay be presented as 3D. Further, in the 3D mode, 2D content may bepresented as flat, or may be converted to 3D.

Aspects of the present invention provide advantages over conventional3D/2D video imaging system, as will now be described.

One advantage deals with transitioning between modes. In particular,when tuning, each transition between TV channels with different 2D and3D formats will cause the video unit, e.g., television, toresynchronize. Each video unit will handle this event differently, butit will always be an unpleasant transition. In accordance with aspectsof the present invention, resynchronization only occurs when the modesof operation are changed. At the same time, a user may want to put on orremove 3D glasses (when using or not using, as the case may be), so theresynchronization occurs at a more acceptable time.

Another advantage deals with the user interface geometry. While tuned to3D channels, the user interface graphics are rendered above the video.Also, while tuned to 2D channels, the user interface graphics arerendered on the same plane as the video. Currently, as you tune andtransition between 2D and 3D channels, the graphics of the UserInterface hops into and out of the video plain. In accordance withaspects of the present invention, the graphics geometry stays in apersistent mode, selected by the user.

Another advantage deals with presenting 2D EAS (Emergency Alert System)during a 3D program. Typically, EAS content is presented in 2D.Currently, if you are watching a 3D channel, the TV will be switched to2D when EAS content is displayed, causing a re-synchronization and amomentary loss of audio/video. In accordance with aspects of the presentinvention, the EAS can be in any format and it will be converted to thecurrent mode's format, selected by the user, avoiding the loss ofaudio/video content.

Another advantage deals with the insertion of advertisements. Inparticular, the existing design requires that inserted advertisementsmatch the preceding content or a re-synchronization and graphicstransition will occur both at the beginning of the inserted clip andafter returning back to the initial program. In accordance with aspectsof the present invention, inserted advertisements will be converted tomatch the format of the current output mode. A single advertisement clipcan be inserted into any program, regardless of 3D format.

Another advantage deals with making mpeg stills cheaper and easier touse. In particular, with the existing design, mpeg stills to bedisplayed must match the preceding content or a re-synchronization andgraphics transition will occur both at the beginning of the insertedclip and after returning back to the initial program. In accordance withaspects of the present invention, mpeg stills can be in any format andwill be converted to match the current mode's format. This makes thedistribution and storage of mpeg stills simpler and cheaper.

Another advantage deals with alleviating issues caused by tuner swappingand DVR (Digital Video Recorder) operations. In particular, tunerswapping and DVR operations can cause 2D/3D format transition. Forexample, this can occur when swapping between 2D and 3D channels,switching between a live channel and recorded content and playback andrewind of recorded content that crosses 2D/3D transitions. Currently,each transition will re-synchronize the TV, and cause the graphicsgeometry to change. In accordance with aspects of the present invention,the source content will be converted to match the current output 3Dformat.

Another advantage allows users to watch content presented in 3D even if3D glasses are unavailable. Currently, if a user wishes to watch contentthat is only presented in a 3D format, the user must have 3D glasses. If3D glasses are unavailable, the user will not be able to watch thatcontent clearly. In accordance with aspects of the present invention,the user would select the 2D output mode on the set-top box and the 3Dcontent would be presented in a 2D format.

Another advantage deals with duplicating channels for 2D and 3D.Currently service providers must duplicate channels, one being in 2Dformat and on being in a 3D format. This expands the number of channelsthe user has available to choose from and requires more bandwidth. Inaccordance with aspects of the present invention, the service providerwould only need to provide on format for each channel and the set-topbox would convert the content to the format the user selects. This wouldsave bandwidth and make the channel lineup more compact and simple.

The foregoing description of various preferred embodiments of theinvention have been presented for purposes of illustration anddescription. It is not intended to be exhaustive or to limit theinvention to the precise forms disclosed, and obviously manymodifications and variations are possible in light of the aboveteaching. The example embodiments, as described above, were chosen anddescribed in order to best explain the principles of the invention andits practical application to thereby enable others skilled in the art tobest utilize the invention in various embodiments and with variousmodifications as are suited to the particular use contemplated. It isintended that the scope of the invention be defined by the claimsappended hereto.

What is claimed is:
 1. A system for controlling a presentation ofcontent, the system comprising: a computer configured to: cause adisplay to display a first piece of content in a first format; determinethat a user is switching between presentations of different pieces ofcontent; while it is determined that the user is switching betweenpresentations of different pieces of content: determine that a secondpiece of content is in a second format that is different from the firstformat; cause the display to display the second piece of content in thefirst format; after causing the display to display the second piece ofcontent in the first format, determine that the user has stoppedswitching between presentations of different pieces of content; and inresponse to determining that the user has stopped switching betweenpresentations of different pieces of content, cause the display todisplay the second piece of content in the second format.
 2. The systemof claim 1, wherein the first format is 3D side-by-side full resolutionand the second format is 3D side-by-side half resolution.
 3. The systemof claim 1, wherein the first format is 3D side-by-side full resolutionand the second format is 3D top-bottom.
 4. The system of claim 1,wherein the computer is further configured to convert first video datacorresponding to the second piece of content in the first format tosecond video data corresponding to the second piece of content in thesecond format based at least on a first resolution associated with thefirst format and a second resolution associated with the second format.5. The system of claim 1, wherein determining that the user has stoppedswitching between presentations of different pieces of content is basedon a determination that a predetermined duration of time has elapsed. 6.The system of claim 1, wherein the computer is further configured to:determine that a third format is not supported by the display; and inresponse to determining that the third format is not supported by thedisplay, select the second format that is supported by the display. 7.The system of claim 1, wherein the computer is further configured to:identify one or more graphics to be presented in connection with thesecond piece of content; combine the one or more graphics with firstvideo data corresponding to the second piece of content in the secondformat to create second video data; and when causing the display todisplay the second piece of content in the second format, cause thedisplay to display the second video data such that the one or moregraphics are overlaid on the second piece of content.
 8. A method forcontrolling a presentation of content, comprising: causing a display todisplay a first piece of content in a first format; determining that auser is switching between presentations of different pieces of content;while it is determined that the user is switching between presentationsof different pieces of content: determining that a second piece ofcontent is in a second format that is different from the first format;causing the display to display the second piece of content in the firstformat; after causing the display to display the second piece of contentin the first format, determining that the user has stopped switchingbetween presentations of different pieces of content; and in response todetermining that the user has stopped switching between presentations ofdifferent pieces of content, causing the display to display the secondpiece of content in the second format.
 9. The method of claim 8, whereinthe first format is 3D side-by-side full resolution and the secondformat is 3D side-by-side half resolution.
 10. The method of claim 8,wherein the first format is 3D side-by-side full resolution and thesecond format is 3D top-bottom.
 11. The method of claim 8, wherein themethod further comprises converting first video data corresponding tothe second piece of content in the first format to second video datacorresponding to the second piece of content in the second format basedat least on a first resolution associated with the first format and asecond resolution associated with the second format.
 12. The method ofclaim 8, wherein determining that the user has stopped switching betweenpresentations of different pieces of content is based on a determinationthat a predetermined duration of time has elapsed.
 13. The method ofclaim 8, wherein the method further comprises: determining that a thirdformat is not supported by the display; and in response to determiningthat the third format is not supported by the display, selecting thesecond format that is supported by the display.
 14. The method of claim8, wherein the method further comprises: identifying one or moregraphics to be presented in connection with the second piece of content;combining the one or more graphics with first video data correspondingto the second piece of content in the second format to create secondvideo data; and when causing the display to display the second piece ofcontent in the second format, causing the display to display the secondvideo data such that the one or more graphics are overlaid on the secondpiece of content.
 15. A non-transitory computer-readable mediumcontaining computer executable instructions that, when executed by aprocessor, cause the processor to perform a method for controlling apresentation of content, the method comprising: causing a display todisplay a first piece of content in a first format; determining that auser is switching between presentations of different pieces of content;while it is determined that the user is switching between presentationsof different pieces of content: determining that a second piece ofcontent is in a second format that is different from the first format;causing the display to display the second piece of content in the firstformat; after causing the display to display the second piece of contentin the first format, determining that the user has stopped switchingbetween presentations of different pieces of content; and in response todetermining that the user has stopped switching between presentations ofdifferent pieces of content, causing the display to display the secondpiece of content in the second format.
 16. The non-transitorycomputer-readable medium of claim 15, wherein the first format is 3Dside-by-side full resolution and the second format is 3D side-by-sidehalf resolution.
 17. The non-transitory computer-readable medium ofclaim 15, wherein the first format is 3D side-by-side full resolutionand the second format is 3D top-bottom.
 18. The non-transitorycomputer-readable medium of claim 15, wherein the method furthercomprises converting first video data corresponding to the second pieceof content in the first format to second video data corresponding to thesecond piece of content in the second format based at least on a firstresolution associated with the first format and a second resolutionassociated with the second format.
 19. The non-transitorycomputer-readable medium of claim 15, wherein determining that the userhas stopped switching between presentations of different pieces ofcontent is based on a determination that a predetermined duration oftime has elapsed.
 20. The non-transitory computer-readable medium ofclaim 15, wherein the method further comprises: determining that a thirdformat is not supported by the display; and in response to determiningthat the third format is not supported by the display, selecting thesecond format that is supported by the display.
 21. The non-transitorycomputer-readable medium of claim 15, wherein the method furthercomprises: identifying one or more graphics to be presented inconnection with the second piece of content; combining the one or moregraphics with first video data corresponding to the second piece ofcontent in the second format to create second video data; and whencausing the display to display the second piece of content in the secondformat, causing the display to display the second video data such thatthe one or more graphics are overlaid on the second piece of content.